1. Field of the Invention
The invention relates to a radio frequency semiconductor circuit apparatus with an integrated antenna.
2. Description of the Related Art
While compact information terminals such as a cellular phone and a personal digital assistance (PDA) are getting sophisticated at increasing speed, miniaturization and weight saving are indispensable for these products to be accepted in the market. On this account, not only functional and performance sophistication but also miniaturization is even required of the semiconductor circuits to be used in these compact information terminals.
For example, in mobile communication terminals for transmitting and receiving radio frequency signals in the form of electromagnetic waves, including cellular phones, Personal Handyphone Systems, and wireless cards, the miniaturization and integration of the semiconductor circuits to be used inside are significant challenges. These mobile communication terminals incorporate an antenna inside as well as a radio frequency circuit. If the antenna and the radio frequency circuit are arranged separately, the packaging area can be increased to preclude meeting the requirement for the miniaturization of the mobile communication terminals.
To reduce the packaging area, there have thus been proposed techniques for forming a radio frequency circuit and an antenna integrally on a single module.
For example, Japanese Patent Laid-Open Publication No. Hei 7-176946 (hereinafter, referred to as patent document 1) discloses the technology of forming and laminating an antenna and a radio frequency circuit in the same planar process.
Moreover, in Japanese Patent Laid-Open Publication No. Hei 11-11055 (hereinafter, referred to as patent document 2), an antenna conductor is formed on and integrated with a base on which electronic parts are arranged.
According to the technology described in patent document 1, the antenna and the radio frequency circuit are formed in an identical planar process. This has made it difficult, however, for these components to be merged with other semiconductor chips and chip parts. According to the technology described in patent document 2, the antenna consisting of a single wiring conductor layer must be formed on the base on which the electronic parts are arranged. Since the proximity of the antenna and the electronic parts causes limitations on the design pattern, there has been the problem that the antenna is hard to sophisticate in performance.